AC Joint Inury

The AC (acromioclavicular) joint is where the shoulder blade (scapula) meets the collarbone (clavicle). The highest point of the shoulder blade is called the acromion. Strong tissues called ligaments connect the acromion to the collarbone, forming the AC joint.

Most AC Joint injuries are treated conservatively using various combinations of strengthening exercises, following the immobilisation phase, once pain permits. Surgery is usually reserved for cases where there is a complete dislocation of the AC Joint (Grade 3), or in cases where a less severe injury fails to respond adequately to conservative treatment.

Anatomy

The Acromioclavicular Joint, or AC Joint, is one of four joints that comprises the Shoulder complex. The AC Joint is formed by the junction of the lateral clavicle and the acromion process of the scapula and is a gliding, or plane style synovial joint. The AC Joint attaches the scapula to the clavicle and serves as the main articulation that suspends the upper extremity from the trunk.

The primary function of the AC Joint is:

To allow the scapula additional range of rotation on the thorax.

Allow for adjustments of the scapula (tipping and internal/external rotation) outside the initial plane of the scapula in order to follow the changing shape of the thorax as arm movement occurs.

The joint allows transmission of forces from the upper extremity to the clavicle.

Symptoms

  • Pain at the end of the collar bone.
  • Pain may feel widespread throughout the shoulder until the initial pain resolves; following this, it is more likely to be a very specific site of pain over the joint itself.
  • Swelling often occurs.
  • Depending on the extent of the injury, a step-deformity may be visible. This is an obvious lump where the joint has been disrupted and is visible on more severe injuries.
  • Pain on moving the shoulder, especially when trying to raise the arms above shoulder height.

Causes

An AC Joint injury often occurs as a result of a direct blow to the tip of the shoulder from, for example, an awkward fall, or impact with another person. This forces the Acromion Process downward, beneath the clavicle. Alternately, an AC Joint injury may result from an upward force to the long axis of the humerus (upper arm bone) such as a fall which directly impacts on the wrist of a straightened arm. Most typically, the shoulder is in an adducted (close to the body) and flexed (bent) position.

Diagnosis

Firstly, for the diagnosis of scapula winging your doctor will look at the shoulder blades for any clear obvious signs of winging. Some patient’s scapula bone may be more visible than others and have distinct scapula winging. The doctor may also ask you to perform arm/ shoulder movements to examine the range of movement and stability at the joint.

One of the main tests that are used to aid in the diagnosis of scapula winging is the serratus anterior test. This is where the patient is asked to face a wall, standing about two feet from the wall and then push against the wall with flat palms at waist level. This test is carried out to identify if any damage is done to the thoracic nerve causing the scapula to wing.

Treatment

The traditional literature supports non-operative treatment for grade I and II injuries. Patients with grade IV, V and VI injuries benefit from operative treatment, whereas the treatment of grade III injuries remains a controversial issue. 22 Numerous surgical procedures have been described, though there is currently no gold standard for the treatment of AC injuries. The main principle of surgical therapy is accurate reduction of the AC joint in both coronal and sagittal planes. This is achieved either by primary repair or by reconstruction of injured ligaments and maintaining stability to protect this repair or reconstruction. The traditional Weaver-Dunn CA ligament transfer procedure has largely fallen into disfavour today. If the AC joint injury presents within six weeks, it is considered acute. The main goal of treatment is acromioclavicular joint stabilisation. Following techniques are used for stabilisation and reduction of AC joint pain. Whilst you are going through a rehabilitation, strength plan massage can also help with specific soft tissue techniques to eleviate pain and discomfort and inflamation such as lymphatic drainage massage.

Exercises

Initially, complete rest, immobilization and regular application of ice or cold therapy are important to reduce pain and inflammation. Mobility exercises can begin only once shoulder movement is pain-free. This will normally be 7-14 days for grades 1 and 2 sprains. Grade 3 injuries are more frequently treated conservatively, without surgery, but will require an even longer rest/healing period. If the shoulder has been immobilized for a period of time, then it may have lost mobility or range of motion.

  • Pendulum exercises can begin as soon as the ligament has healed, and pain allows. Gently swing the arm forwards, backward, and sideways whilst lying on your front or bent over as seen opposite.
  • Gradually increase the range of motion. Repeat this with your arm swinging from side to side as well. Aim to reach 90 degrees of motion in any direction.
  • Front shoulder stretch
  • External rotation stretch
  • Isometric exercises – Strengthening should initially be isometric. This means contracting the muscles without movement.

Resistance band exercises for AC joint sprain:

  • Internal Rotation
  • External Rotation
  • Abduction/lateral raise

Prevention

  • Wearing protective strapping to support a previously injured AC Joint, particularly in contact sports or sports where full elevation of the arm is not so important. Protective padding is also used in sports such as rugby.
  • Warming up, stretching and cooling down.
  • Participating in fitness programs to develop strength, balance, coordination and flexibility.
  • Undertaking training prior to competition to ensure readiness to play.
  • Gradually increasing the intensity and duration of training.
  • Allowing adequate recovery time between workouts or training sessions.

If you feel like you may have an AC Joint injury and would like to know more, please contact our specialist team made up of Physiotherapists and Sports Therapists who deal with these kind of injuries all the time. Alternatively you can make a booking online directly.

Rotator Cuff Strain

In the rotator cuff region there are four muscles, tendons and ligaments, surrounding the shoulder which provide added stability to the shoulder joint. This structure helps to keep the bone securely placed into the socket. Injury to the rotator cuffs can cause an ache like pain in the shoulder. This may lead to a feeling of muscle weakness and inability to lift the shoulder above the head. 

Rotator cuff injuries are most commonly presented in people regularly exposed to overhead movements, such as painters, carpenters and builders. Individuals who suffer from this injury can usually manage their symptoms, through sports massage and specific exercises focusing on the rotator cuff muscle region. However, if not treated correctly, further injury to the area may occur such as a complete tear, which may result in surgery.

Anatomy

The rotator cuffs are made up by four muscles, these are the supraspinatus, infraspinatus, teres minor and subscapularis. These muscles aid in keeping the upper arm and shoulder into the socket with stability. They also each allow specific movements at the shoulder joint. The group of four muscles all originate within the shoulder blade, but all insert into different portions of the upper arm bone. 

Supraspinatus: This muscle originates at the supraspinous fossa; the muscle belly passes laterally over the acromion process and inserts into the greater tubercle of the humerus bone. This muscle allows the first 15 degree’s movement of abduction, after this the deltoid and trapezius muscles will then allow further motion. 

Infraspinatus: The origin of the infraspinatus is the infraspinatus fossa, and the insertion is also the greater tubercle of the humerus. The motion created by this muscle is lateral rotation of the shoulder, moving the arm away from the centreline of the body. 

Teres Minor: A small narrow muscle on the back of the shoulder blade which sits underneath the infraspinatus. The origin is the lateral boarder of the scapula. This muscle contributes to external rotation of the arm of the body. 

Subscapularis: This rotator cuff is the strongest and largest out of the three listed above. This muscle originates at the subscapularis fossa and inserts into the lesser tubercle of the humerus. The subscapularis allows greater motion at the shoulder and mainly aids in allowing medial rotation of the arm. 

Symptoms

Common symptoms of possible rotator cuff strain include:

  • Dull ache 
  • Difficulty lifting arm over head 
  • Weakness around the shoulder
  • Disturbed sleep
  • The constant need to use self-myofascial techniques 

Causes

There are a few common risk factors of why rotator strain may occur:

  1. Family History: There may be family history of rotator cuff injuries which may make certain family members more prone to having the injury than others. 
  2. The type of job you do: Individuals who work in construction or manual labour who have repetitive overhead movement of the shoulder could damage the rotator cuff overtime. 
  3. Age: As you get older joints and muscles become weaker, meaning you may be more prone to injury overtime. 

Diagnosis

To diagnose a rotator cuff strain a physical examination will be carried out by a doctor or a physiotherapist. Firstly, they may ask about your day-to-day activities which may determine the seriousness of the injury. The doctor will test the range of movement at the shoulder by getting you to perform movements such as flexion, extension, abduction, adduction and medial and lateral rotation. This will allow the doctor to determine if it is actually rotator cuff strain or whether it may be other conditions such as impingement or tendinitis. 

Imaging scans such as X-Ray’s may also be used to see if there is any abnormal bone growth within the joint, which may be causing the pain. 

Treatment

Treatments for rotator cuff injuries can be non-surgical or surgical. Tendinitis may occur over time from the repetitive strain placed around the joint, so it is important to treat the affected area. 

  • Apply a cold compress/ ice to the effected area to reduce swelling
  • Heat packs can be used to reduce swelling 
  • Resting the affected area 
  • Inflammatory medication such as ibuprofen and naproxen 
  • Reduce the amount of repetitive movement to the joint
  • Don’t lift the arm overhead

Exercises

  • 1. Doorway Stretch

    • Purpose: Stretches the chest and shoulder muscles, helping to alleviate tension and improve flexibility in the shoulder joint.
    • How to Perform:
      • Stand in a doorway and place your arms on the door frame with elbows at 90 degrees and your hands slightly above head level.
      • Step forward with one foot, gently leaning into the doorway until you feel a stretch in the front of your shoulders and chest.
      • Hold for 20-30 seconds and relax.

    2. External Rotation with Weight

    • Purpose: Strengthen the rotator cuff muscles, particularly the infraspinatus and teres minor, which are responsible for external rotation of the shoulder.
    • How to Perform:
      • Lie on your side with your elbow bent at 90 degrees, holding a light weight in the top hand.
      • Keep your elbow close to your body and rotate your forearm upward, lifting the weight.
      • Slowly lower the weight back down and repeat before switching sides.

    3. High to Low Rows with Resistance Band

    • Purpose: Strengthen the muscles of the upper back and shoulder, improving stability and support for the rotator cuff.
    • How to Perform:
      • Anchor a resistance band above shoulder height.
      • Hold the band with both hands and step back to create tension.
      • Pull the band down and back toward your hips, squeezing your shoulder blades together.
      • Slowly return to the starting position and repeat.

    4. Reverse Fly’s

    • Purpose: Target the posterior deltoids and the upper back muscles, which help support and stabilise the shoulder joint.
    • How to Perform:
      • Stand with feet hip-width apart and a slight bend in your knees, holding a light weight in each hand.
      • Bend forward at the hips with your back flat and arms hanging down.
      • Raise your arms out to the sides until they’re level with your shoulders, squeezing your shoulder blades together.
      • Lower your arms back down and repeat.

    5. Lawn Mower Pull with Resistance Band

    • Purpose: Strengthen the shoulder and back muscles, mimicking the movement of starting a lawn mower, which engages the rotator cuff.
    • How to Perform:
      • Anchor a resistance band at ground level.
      • Stand with one foot forward and grab the band with the opposite hand.
      • Pull the band up and back diagonally, rotating your torso and mimicking the motion of starting a lawn mower.
      • Slowly return to the starting position and repeat before switching sides.

    6. Isometric Internal Rotation

    • Purpose: Strengthen the subscapularis muscle of the rotator cuff without moving the shoulder, which is helpful when active movement is painful.
    • How to Perform:
      • Stand next to a wall with your elbow bent at 90 degrees, holding a small towel or cushion between your forearm and the wall.
      • Press your forearm into the wall, engaging the internal rotators of the shoulder.
      • Hold the tension for 10-15 seconds, then relax and repeat.

    7. Isometric External Rotation

    • Purpose: Strengthen the external rotators (infraspinatus and teres minor) of the rotator cuff without movement, useful for stabilising the shoulder.
    • How to Perform:
      • Stand next to a wall with your elbow bent at 90 degrees, this time with the back of your hand pressing against the wall.
      • Push your hand outward into the wall, engaging the external rotators.
      • Hold the tension for 10-15 seconds, then relax and repeat.